
<html>
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

<script>


    function fb(n){
        if (n == 1|| n == 2){
            return 1;
        }else {
            return fb(n - 1) + fb(n-2);
        }
    }
    console.log(fb(25));
</script>
</body>
</html>